You will never see a visually consistent operating system again, the material conditions that allowed for older Windows and Mac OS versions to be consistent no longer exist. The user base for desktop computers is no longer growing, so the investment into new desktop UI technologies is largely in technologies like Electron and SwiftUI that allow developers to cut costs by reusing their existing web and mobile interfaces for desktop software. The focus on cross-platform development means that developers are far more concerned about making their software look consistent across all platforms than they are about whether their software looks native on each platform it supports.